Grinder.



H. E. TIDMARSH.

GRINDER.

APPLICATION FILED MAR. 31. 1916.

2 SHEETS-SHEET I.

Patented July 3, 1917.

mamm.

M/VE/VTOR W 8.3mm

A TTOR/VEYS H. E. TIDMARSH.

GRINDER.

APPLICATION FILED MAR-31.1916.

Patented July 3, 1917..

2 SHEETS-SHEET 2.

A TI O/WE VS pnrcrnn snares ATENT onnrcn HARRY E. TIDMARSH, OF BANGOR, MAINE, ASSIGNOR OF ONE-HALF TO UNION IRON WORKS, OF BANGOR, MAINE, A. CORPORATION OF MAINE.

GRINDER.

Specification of Letters Patent.

Patented July 3, 1917.

To all whom it may concern:

Be it known that I, HAR YE. TIDMARSH, a citizen of the United States, residing at Bangor, county of Penobscot, and State of Maine, have invented certainnew and useful Improvements in Grinders; and I do hereby declare the following to be a full, clear, and

exact description of the invention, such asv will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in grinders for the production of Wood pulp.

In the production of suchwool pulp bymechanical grinders, where two or more pockets are arranged at different angles upon the same stone, the pulp produced at one pocket tends to be carried around with the stone and to pass beneath the other pockets, where it is reground. As a. result, the pulp thus reground tends to become finer than that produced in the succeeding pockets with resulting lack of uniformity in the pulp as a whole. Furthermore, the capacity of the other pockets is decreased because of the grinding action used up in regrmdmg the pulp already produced.

It is the primary object of the present in- Vention to overcome these disadvantages and to provide for the removalof the pulp produced in each pocket so that it will not pass to the next pocket and be there reground.

While the invention is capable of many mechanical embodiments, I have found the construction illustrated in the accompanying drawings to be an advantageous one, and the invention will accordingly be more fully described in connection therewith, but it is intended and understood that the invention will be illustrated by, but is not limited to, the specific embodiment thus illustrated and described.

In the accompanying drawings,

Figure 1 shows a three-pocket grinder, partly in elevation and partly in section, with the invention embodied therein;

Fig. 2 shows the grinder partly in elevation and partly in transverse vertical sec tion, the view being taken substantially along the line 22 of Fig. 1;

Fig. 3 is a plan view of the plow or scraper; and

Fig. 4 is a perspective view of the plow or scraper.

In the grinder illustrated, the rotating grindstone 1 is mounted upon the shaft 2 in any suitable or preferred manner, and the shaft is in turn adjustably supported in bearings 8 and driven by any suitable means. Surrounding the stone at its ends, and spaced apart therefrom, is the housing l upon which are suitably mounted pockets 5 of any suitable construction. Within the pockets are plunger-s 6 for feeding the wood against the stone under the proper pressure. The plungers are themselves operated by means of pistons 7 within the cylinders 8, in the usual manner.

'lWlounted upon the housing d between the pockets are the frame or supporting members 9,-from which the pockets are adjust ably supported by bolts or rods 10. Also, adjustably attached to the pockets are the bolts 11, which carry at their lower ends the plows or scrapers 12. By reference to Figs. Sand 4:, it will be seen that these plows or scrapers are somewhat V-shaped in form and are supported by means of supporting and stiffening means 13 on the lower ends of the bolts 11. The scrapers 12 may be either of wood or of metal, and may be varied in size and shape, as will be readily understood.

WVith the construction shown, and with both the bolts 10 and 11 adjustable, the scrapers can be adjusted independently of the pockets, to make up for wear, and also they can be adjusted with the pockets as it becomes necessary to adjust the pockets themselves nearer to the stone, as the stone Wears away.

It will be noted that the scrapers are arranged between the pockets and are attached to one side of the pockets on the outside. The arrangement is such that the scraper can be attached to either side of the pocket in substantially the same manner.

By reference to Fig. 2, it will be seen that the scrapers or plows 12 are arranged to remove the pulp from the stone between the pockets and to discharge the pulp into the space between the stone and the housing, the spacing away of the housing from the stone at its ends permitting this discharge to take place.

It will accordingly be seen that the pulp is removed from the stone after it has been produced in each pocket so that the next pocket will. be unobstructed by the pulp already produeed and so that such pocket can exert its maximum grinding action upon accordingly enables the quantity of pulp to be increased, thus increasing the capacity of the grinders; and it also enables a more,

uniform quality of pulp to be produced.

It will be readily understood that the invention is of general application to mechanical grinders of many different types and constructions; and that these grinders can be operated in substantially the same manner as at present, except for the modifications and advantages resulting from the removal of the pulp produced in each pocket independently' rlccordingly while I have illustrated one construction which has been found in practice to be advantageous, nevertheless 'I do not limit myself to the particular construction illustrated and described, inasmuch as I consider the invention of broader and more general application.

What I claim is:

1. A grinder for the production of wood pulp comprising a rotary grindstone, a plurality of pockets arranged around the stone for receiving the Wood to be ground and provided with means for feeding the wood against the stone, and scrapers arranged between the pockets and adjustable therewith with respect to the stone, said scrapers being arranged to remove the pulp produced and thereby prevent the same from passing to the next pocket and being reground; substantially as described.

2. A grinder for the production of wood pulp comprising a rotary grindstone, a plurality of pockets arranged around the stone for receiving the wood to be ground and provided with means for feeding the wood against the stone, and scrapers arranged between the pockets and adjustable with respect to both the pockets and the stone, said scrapers being arranged to remove the pulp produced and thereby prevent the same from passing to the next pocket and being reground; substantially as described.

3. A grinder for the production of wood pulp comprising 'a rotary grindstone, a plu pockets arranged around the stone for receiving the wood to be ground and having means for feeding the wood against the stone, and scrapers arranged between the pockets and adjustable with respect to both the pockets and the stone, the adjusting means being outside of the casing, said scrapers being arranged to remove the pulp produced and thereby prevent the same from passing to the next pocket and being reground; substantially as described.

5. A grinder for the production of wood pulp comprising a rotary grindstone, a casing therefor provided with a plurality of pockets arranged around the stone for receiving the Wood to be ground and having means for feeding the wood against the stone, and scrapers arranged between the pockets for removing the pulp produced and thereby preventing the same from passing to the next pocket and being regro-und, each of said scrapers beingrmounted'upon one of the pockets and being adjustable with respect thereto, the adjusting means being located without the casing; substantially as described.

In testimony whereof I afliX my signature.

HARRY E. TIDMARSH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G.

ing therefor provided with a plurality of' 

